Buttonhole sewing machine



April 25, 1933. c. A. o. GRIP 5 35 BUTTQNHOLE? SEWING MACHINE Filed May24, 1932 3 Sheets-Sheet 1 Fig.1.

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A'TTys.

April 25, 1933.

C. A. O. GRIP BUTTONHOLE SEWING MACHINE Filed May 24, 1932 Fig.2.

3 Sheets-Sheet 2 732 Fig.3.

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BUTTONHOLE SEWING MACHINE April 25, 1933. Q O GRlP 1,905,854

Filed May 24, 1932 3 Sheets-Sheet 3 67 I Inv e nTor. Cori A.Q.Gr\p

Patented Apr. 25, 1933 UNITED STATES PATENT pnea-i,

CARL a o. GRIP, or NEWTONVILLE, MASSACHUSETTS, ASSIGNOR "To; 'REEC'EBUTTON HOLE MACHINE COMIANY, F BOSTON, MASSACHUSETTS, CORIfOR-A- TION OFMAINE BUTTONHOLE SEWING MACHINE Application filed May 24, 1932. SerialNo. 613,217.

This invention relates to buttonhole sewing machines and has for one ofits objects to provide'a novel means for pulling off a length of underthread at the GIICl'Of the sewing operation preparatory to cutting theunder thread and stay cord. I

Another objectof the invention is to provide improved means for guidingthe reciprocating movements of the under thread mechanism which ismounted on the turret.

In order to give an understanding of the invention I have illustrated inthe drawings a selected embodiment thereof which Wlll now be describedafter which the novel features will be pointed out in the appendedclaims.

Fig. 1 is a side view of a portion of abuttonhole sewing machineembodying the invention;

Figs. 2 and'3 are views of the turret and the under thread mechanismcarried thereby;

Fig. 4 is a fragmentary sectional view showing the operation of theunder thread pull-off Fig. 5 is a sectional view of the under threadpull-off arm taken on substantially the line 7-7, Fig. 3; h

' Fig. 6 is a section on the line 8 8, Fig. 5;

Fig. 7 is a section on the line 11, Fig. 2 looking upwardly in saidfigure;

Fig. 8 is a fragmentary view illustrating the operation of the underthread pull-off arm;

Fig. 9 is a fragmentary view showing a slightly different'way ofmounting the pullolf arm than that shown in Figs. 5 and 6;

F ig..10 is a section on the-line 1010, Fig. 9 but illustrating thepull-off arm in eleva,- tion.

The buttonhole sewing machine herein illustrated has theusuaIwork-holding means which is mounted on the bed plate 1 and the usualstitch-forming mechanism which is carried by a stitch frame indicatedgenerally at 2. The stitch frame and the bed plate have a movementrelativeto each other during the sewing on the buttonhole andalso afurther relative movement to'carry the parts from stitching. tobuttonhole cutting position as usual in buttonhole'sewing' machines ofthis type;

' jThe work-holding clamps 3 by which the, work 4 is'clamp'ed againstthe mats5 I which arecarried by the clamp plates "6, the latter beingremovably mounted on the bedplate'las usual.

The "stitch-forming mechanism comprises 'the usual needle 7 carried by aneedle bar 8 which is mounted for "reciprocation in the stitch frame 2,and also under threadmecha- 'nism which is carried by the turret-9 thatis rotatively mounted in the portion 10 of the stitch frame on theopposite side of the work from the needle.

Theturret 9 carries the usual throat plate or'butt0n 11 which isprovided: "with the sewing op'ening 12 through which the' needleTOperates. 'fl

The under thread mechanism is of the type which comprises the loopers l3and the loop spreaders 14, said loopers and spreaders being carried onthe oscillatinglooper-carrying block 15 which is mounted to oscillateupon a stud 16. The means for oscillating the looper-carrying block 15issimilar to that usually employed in buttonhole sewing machines ofthistype'f Said block isconnected by a link 17 to a hollow spindle18"wliich reciprocates vertically in the turret 9. 'Said spindle isactuated by a lever 19 pivoted-to the portion 1'0 of the frame at 20and-connected by a link 21 to" a suitably actuated lever which gives thelever 19- its required oscillating movement. 1

The loop Spreaders are actuated as usual by means'of a spreader wedgeindicated at 22 whichisgalso mounted for oscillation on thetstud 16 andis connected by a link 23 to aspindle 24 which extends axially throughthe spindle 18'and which is actuatedbya lever'25 pivoted at 26to'theportion 10 of the stitch frame, said lever being connected by-alink 27 to a suitably actuated lever. It will be "understood by thosefamiliar with buttonhole sewing machines that; during the sewing of thebuttonhole, the stitch frame 2. andthe'work-holding means will havearelative feeding movement and when the sewing 011 the means compriseswork buttonhole has been com- 7 pleted and the stitch-forming mechanismhas come to rest with the needle retracted as shown in Fig. 1, saidstitch frame and workholding means will have a further relative movementto carry the parts from stitching to buttonhole-cutting position, thebuttonhole-cutting position being indicated by the dotted lines inFig. 1. During this further movement the under thread 28 Which-is led tothe work from the threaded looper through the sewing opening 12 of thethroat plate 11, and the stay cord 29 which is also led to the workthrough the sewing opening 12, will be drawn out through the sewingopening as illustrated in Fig. 4 so that there will be a length of thethread and the stay cord extending from the stitched buttonhole 30 tothe throat plate 11 and lying on the opposite side of the work from theneedle.

One feature of the invention relates to a novel pull-0E device foracting on the length of under thread between the throat plate and thework to pull off a length of under thread from the source of supplysufiicient to enable the first stitch on the next buttonhole to beproperlyformed.

The underthread pull-oif is in some respects similar to that shown inco-pending application of Joseph Pikul, Serial No. 525,376, filed March26, 1931. 'Asillustrated in Figs. 4 and 5 it is mounted on the turretand comprises a pull-off arm 3lpivotally mounted on the stud 16 andprovided at its upper end with a pull-off hook 32 adapted during theoperative swinging movement of the arm 31 toward the left in Fig. 3 toengage the under thread 28 between the throat plate 11 and the work andthereby pull a ength of under thread through the throat plate from thesource of supply, it being understood that the tension on the underthread will be released at thistime by mechanism usually employed forthat purpose thereby toallow the under thread to be freely drawn fromthesource of supply. The amount of under thread which is thus pulledthrough the throatplate is sufiicient so that when the under thread hasbeen cut close to the work byany suitable thread-cutting device therewill be pro ecting from thethroat plate a sufficient length of underthread properly to form the first stitch on the next buttonhole.

This pull-off arm 31 is normally held in its inoperative position by aspring 85 which isconnected at one end to said arm and at the ,other endto an anchorage 96 carried by the turret 9. Said pull-off arm 31 isshown in Figs. 5 and 6 as provided at its lower end with'a split hub 33which encircles and is clamped to, a sleeve 34 that is mounted forturning movement on an extension .35 of the stud 16. The split hub 33 isclamped to the sleeve 34 by means of a clamping screw 36. The sleeve 34is provided with a slot 37 in whichis received. a stop pin 38 carried bythe stud extension 35, said stop pin and slot limiting the extent of thespring-impelled return turning movement of the sleeve about the stud andconsequently stopping the arm 31 in its proper inoperative position.

The throat plate 11 herein illustrated is constructed similar to thatshown in the machine illustrated in the above-mentioned copendingapplication Serial No. 525,376, in that it has a slot 39 into which theunder thread 28 is received when the parts have been moved intobuttonhole-cutting position as shown in Fig. 4 the cord 29 at such timeresting on top of the throat plate and thus being above theportion ofthe under thread which extends from the throat plate to the work. henthe pull-off arm is given its operative movement from the full to thedotted line position Fig. 8 the hook 32 engages the under thread 28 butdoes not engage the cord 29 sothat the pull-off, arm acts only on theunder thread. 4 y v The. pal-off arm is given its operative movement bythe reverse rotative movement of the turret 9 which occurs after thesewing of the buttonhole has been completed. Those who are familiar withbutton hole sewing machines will understand that in sewing around theeye end of the buttonhole the turret will have a half rotation andthatafter the sewing on the buttonhole has been completed and thestitch-forming mechanism has come to restand either during or directlyafter the movement by which the stitch frame and work-holding means arecarried into buttonhole-cutting position the turret will be given areverse rotative movement to bring it back into initial position readyfor the stitching on the next buttonhole.

The pull-0E arm 31 is of the type which is actuated by this reverserotative 1nove inent. For this purpose the hub 33 of said pull-off armhas adjustably mounted thereon a depending tail 40 which extends downthrough the upper ring 41 of the turret and is adapted to engage a dog42 carried on the under side of thebearing portion 43 of the stitchframe in which the turret is mounted. This dog is shown as pivotallymounted on a stud 44 carried by the portion 43 of the stitch frame andis acted on by a spring 45 which normally holds it in its operativeposition shown in Fig. 7 in which it rests against a stop'pin 46. Whenin this position the end 47 thereof is in the path of movement of thelaterally-bentend 48 of the tail 40. At the time that the stitch-formingmechanism comes to rest the turret will be so positioned .in'its bearingthat the laterally-extending end 48 of the tail'40 will be in closeproximity to the end 47 of the dog 42. and as the turret is given itsreverse rotative movement in the direction of the arrow in Fig. 7 theend 48 of the tail 40 will strike the end 47 of the dog .42 so thatduring the further rotative movement causingthe pull-off hook 32'itoengage the under thread and pull a'sufiic-ient length there- 5 offromthe source of-supply through the "throat plate.- r 1 As the turretcontinues its rotative movement the end 48 of the tail 40 will wipe over'the end 47 of the dog 42 'and'the spring 85 will then return thepull-off arm toits normal position, which position is determined'by theengagement of the pin 38--with-one end of the slot 37 as previouslymentioned One feature of the present invention relates to means by whichthe amount of thread which is pulled off ma'ybeadjusted according to therequirement of use; This isaccomplished-by providing means whereby thetail 40 may be adjusted vertically with relation to the liub 33. Asshown in F ig; 6 the tail 40 is ma de separately from the hub 33, thelatter having a flat face 49 to whichtheupper end of the tail 40'is adjustablysecured; Said upper end is shown as having a slot 50 thereinthrough which the clamping screw 36 extends, said screw performing thedouble 1 function-f of clamping the hub 33 to the sleeve 34 and alsoclamping the tail 4O t'o' the hub-g 52 is a stud pin fast to the hub33*and occupying the slot below the'clamping screw 36. By loosening thescrew 36 the tail 40'can be adjusted vertically, the screw 36 whentightened serving to clamp the tail in its adjusted position. The pin 52serves to hold the tail firmly in its adjusted position and preventpossible rotation about the clamping screw 36.

The extent of the swinging movement of the pull-01f arm and consequentlythe amount of under thread which is pulled oil depends upon the relativeposition in a vertical direction of the end 48 of the tail and the end47 of the dog, because during the turning movement of the turret the end48 of the tail first engages the end 47 of the dog and then as the tailswings said end 48 wipes over the end 47 of the dog. If the adjustmentis such that the lower edge of the end 48 just barely en- 'gages the end47 of the dog then the tail will wipe over the dog after the arm 31 hashad a slight swinging movement while if the tail 40 is adjusteddownwardly then said tail and the arm 31 will have a greater swingingmovement before the end 48 wipes over the end 47 of the dog. By thissimple means the action of the pull-off arm can be regulated so as topull off the desired amount of under thread at the end of eachbuttonhole.

58 indicates a stay cord guide through which the stay cord is guided tothe throat plate, said guide being of the type which will permit thestay cord to be fed forwardly but will prevent retrograde movementthereof.

In the construction shown in Figs. 5 and 6 the hub 33 of the pull-offarm 31 is clamped 65 to the sleeve 34 which is retained on the head fin64. tobe,

"rotatively mounted thereon, mechanism 35-of'the stud-16 by theengagement of the pin 38 in the slot 37 of the sleeve.

In Figs. 9 and I have shown a slightly difierent construction. Inthisembodiment the pull-off arm is indicated at 31a and it is shownasdetachably secured to a hub member 33a that is rotatively mounted on thehead 35a ofthe stud 16a which forms the 'pivotfor the looper-carryingblock a'nd which corresponds to the stud 16 in Figs. 5 7 land 6.

1 The pull-offar1n31a is shown as'adjustably clamped to an'arm' 61extending from the hub 33a by meansof ascrew62, said pull-off arm havinga slot 63 which permits 0 the pull-off arm to be vertically adjusted.

The hub. 33a'is mounted on the head a of the stud l6a-so as to freelyrotate and it is retained on said head by a retaining fin 64 whichpasses through aslot 65 in the hub 33a and-enters an annular groove 66formed in the head 35a. This locking fin 64is shown as carried by aresilient finger 68 which is secured to the hub 33a by asuitablescrew67. The resiliency ofthe'finger 68 permitsthe Withdrawn: from thegroove 66 thereby permitting the hub 33a to be slipped off from the head35a in case it is desired to remove th'e'hub 33a and pullolf finger.

Iclaim: 1; In a' buttonhole sewing machine, the combination with astitchframe, of a turret stitch-forming including loopers pivotally mounted onthe turret to oscillate about' a commonaxis, a thread pull-off armpivoted co-axially with the loopers and adapted to engage the under.thread to pull; a length thereof from the source of supply, and meanstoactuate the-pull-off arm after the sewing operation is completed.

2. In a buttonhole sewing machine, the combination with work-holdingmeans, of; a

stitch frame, stitch-forming mechanism carried :by the stitchframe andincluding oscillatingloopers operatingon the opposite side of the workfrom theneedle, a turret on which said loopers arepivotally.mounted,anunder thread pull-off arm pivoted-on the turretcoaxial with the loopers, said turret having a rotary movement after thestitching .operation is completed, and means rendered operative by suchrotary movement to actuate the pull-off arm;

3. In a buttonhole sewing machine, the combination with a stitch frame,of a rotary turret mounted thereon, stitch-formingmechanism includingloopers mounted on the turret for oscillating movement,an under thread'pull-oif'arm pivoted co-axially with theloopers said turret having areverserotative movement after the completion of the stitching of thebuttonhole,a"tail depending from the pull-01f arm-and'a dog carried bythe stitch frame adapted to engage said tail during such -130 reve-rserotary movemen thereby to actuate the pull-off arm, 7 i

4. In a buttonhole sewing machine, the combination with a stitch frame,of a rotary turret mounted there n, st tch-forming mechanism includingloopers mounted on the turret for oscillating movement, an under thr adpull-cit arm pivoted co axially with the loopers, said turret having a.reverse rotative movement after the completion of the stitching of thebuttonhole, a dog carried by the stitch frame and a tail depending fromthe pull-off arm and adapted to engage and. wipe over the dog during thereverse rotary movement of the turret thereby to actuate the pnll o-ffarm.

5. In a buttonhole sewing machine, the combination-with a stitchtrame,of a rotary turret mounted thereon, stitch-forming mechanism includingloopers mounted on the turret for oscillating movement, an under threadpull-ofl arm :pivoted co-axially with the loopers, said turret having .areverse rotative movement after the complecan tion of the stitching ofthe buttonhole, a dog carried by the stitch frame and a-tail dependingfrom the pull-off arm and adapted to engage and wipe over the dog duringthe reverse rotary movement of the turret thereby to actuate thepull-off arm, said tail being adjustable vertically thereby to providefor a variation in the amplitude of swinging movement of the pull-offarm and a corresponding variation in the amount of thread vdraw-n ofl',c

,6. In a buttonhole sewing machine, the combination with a stitch frame,of a turret .rotatively mounted thereon, said turretlla-v- .ingva throatplate, stitch-forming mechanism including oscillating loopers pivotallymounted on the turret, an under thread pull- ;ofi' arm pivoted on theturret co-axially with the loopers and adapted to engage the underthread between the throat plate and the work, said. turret having areverse rotary motion at the completion of each buttonhole, and meansrendered operative'by said reverse rotation to actuate the pull-off arm.

7 In a buttonholel sewing machine, the combination with a stitch frame,of a turret rotatively mounted thereon, said turret having a throatplate, stitch-forming mechanism including oscillating loopers pivotallymounted on the turret, an under thread pulloff arm pivoted on the turretcol-axially with the loopers and adapted to engage the under threadbetween the throat plate and rthe work,said turret having a reverserotary motion at the completion of each buttonhole, means renderedoperative by saidreverse rotation to actuate the pull-off arm, and meansfor varying the amplitude of the pulling-oil movement of the pull-ofiarm. 8. In a buttonhole sewing machine, the combination with a stitchframe, of a turret rotatively mounted thereon and havin a verse rotationat the end of each buttonh e,

sti chforming m chanism including a loope arrying block and looperspivotally mounted on the turret, a stu on which said block oscillates,said stud having an extension, :1 thread pu hofi" arm pivota y ou ted onthe stu e en ion andadapted to en gage the under thread to pull a lengthfrom he source of supp y, and mea s. to actuate annular groove, a threadpullsofi'. member a piv tally mo n d on he st d ex ension and d p d tengage the under hread to pull a length from the source of supply andmeans to actuate the pull-off member, and a sprin pressed locking fincarried by said member f and adapted to engage in said groove to re inthe member o h stud- 1 In testimony whereof, I have signed my name tothis specification.

CARL ,A- O- G

